WO2014064209A1

WO2014064209A1 - Method for producing a wood material

Info

Publication number: WO2014064209A1
Application number: PCT/EP2013/072304
Authority: WO
Inventors: Thomas Kuncinger; Cornelia Gradinger; Daniel Stratev
Original assignee: Fritz Egger Gmbh & Co. Og
Priority date: 2012-10-24
Filing date: 2013-10-24
Publication date: 2014-05-01
Also published as: DE102012020842A1; PL2912100T3; LT2912100T; HUE040579T2; EP2912100B1; ES2691426T3; DE102012020842B4; EP2912100A1

Abstract

The invention relates to a method for producing a wood material, wherein a wood-containing preliminary or intermediate product of the wood material is treated with a medium containing microorganisms. The invention further relates to the wood material that can be obtained by the method according to the invention, a medium containing microorganisms for reducing the content of wood extract material, precursor substances of VOCs, and/or VOCs in a material based on cellulose, in particular wood and/or a wood material, and the use of a medium containing microorganisms to reduce the content of wood extract material, precursor substances of VOCs, and/or VOCs in wood or a wood material.

Description

Process for producing a wood-based material

The invention relates to a method for producing a wood-based material and to a microorganism-containing medium for reducing the content of wood extract substance,

Precursors of VOC and / or VOC in a material based on cellulose, in particular wood and / or a wood material. The invention further relates to a

Wood material and the use of a microorganism-containing medium to reduce the content of

Wood extract, precursors of VOC and / or VOC in wood or a wood-based material.

Processes in which the content of wood extract and / or volatile organic compounds (VOC) or their precursors in cellulose-containing materials is reduced are known in principle.

Wood extract is a mixture of different

Wood ingredients which are soluble in solvents, in particular in polar and / or apolar organic solvents and / or water, for example in water, alcohol,

Benzene, hexane, cyclohexane, ether and / or acetone.

Wood extractives, which usually contain about 3% to 10% of the

Make up wood weight, for example

low molecular weight hydrocarbons, terpenes, aromatic and aliphatic acids, alcohols, tannins, dyes, proteins, alkaloids and / or soluble lignins. In particular contains Wood extract typically also VOC and / or VOC precursors.

Wood extractives can significantly degrade the properties of materials used in the woodworking industry, such as the surface properties of the wood, as well as its drying or sizing behavior. Consequently, there is a need to reduce the amount of wood extract in cellulose-containing materials such as wood (especially solid wood), wood-based materials and their precursors or intermediates (especially wood strands,

Wood chips or wood fibers), for example for the

Reduce wood board production. However, the occurrence of wood extractives and in particular the VOC contained therein is also disadvantageous for other reasons. So be in the heat, for example in

Drying steps as commonly used in the wood processing industry, VOC

Precursor substances, such as those in the

Wood extractives occurring unsaturated fats or resin acids, oxidized by thermal induction, wherein VOC are formed. In addition to this, naturally many VOCs, such as those from the

Class of terpenes, contained in wood extractives. The release of VOC, and especially of short-chain aldehydes, often leads to the formation of an unpleasant odor in the end product of wood-based materials. One of the main causes of VOC formation in cellulose-containing materials is the chemical, and in particular the oxidative degradation of wood extractives. Other sources for VOC can be the thermal and / or chemical degradation of

Lignin, hemicellulose or cellulose and / or of resins. The release of VOC is further promoted by an increase in the particle surface in the processing of cellulose-containing products.

In addition to formaldehyde emissions caused by binders, VOC emissions play an increasing role in the

Evaluation of room loads of components and materials made of cellulose-containing materials. The problem here is in particular the release of monoterpenes,

Sesquiterpenes, phenols (especially guaiacol) and low molecular weight aliphatic alcohols and / or aldehydes (especially heptanol and hexanal) emitted from cellulose-containing materials. The emission of VOC is increasingly subject to restrictions due to feared health hazards.

For this reason, there is a great need in the woodworking industry to reduce VOC emissions from

Cellulose-containing materials and products too

to reduce .

There are a number of physico-chemical methods for removing wood extractives or reducing VOC content.

EP 2 181 818 A2 describes inter alia a process for the production of wood fiber materials with reduced VOC emission using a formulation comprising at least one compound for adjusting a neutral to basic pH and at least one complexing agent and as optional further Component contains antioxidants for oxidation protection of fats.

WO 2006/039914 A1 describes the use of alkali metal hydroxides (especially of NaOH), alkali metal carbonates (especially of a ₂ C0 ₃ ), alkali metal sulfites (especially of Na ₂ S0 ₃ ), alkali metal phosphates

(especially of Na ₃ P0 ₄ ), mixtures of the aforementioned

Compounds and ammonia gas (NH ₃ ) to reduce emissions of VOCs from wood-based materials, especially from OSB.

WO 2006/032267 AI describes u. a. the use of alkaline compounds to produce emission-reduced OSB from high-fat conifers. From WO 2009/021702 AI is a treatment method for

Reduction of VOC and formaldehyde emission in wood-based materials is known in which a mixture of i) bisulfite salt; ii) sulfite salt; and iii) optionally urea and

Urea derivatives and iv) optionally alkali, alkaline earth or ammonium hydroxide is used.

From EP 1 852 231 A2 a method for the production of wood materials with reduced VOC emission is known, in which the VOCs with a component A, which may be, for example phenol or resorcinol, in the presence of a

Component B, namely a strong acid or a Friedel-Crafts catalyst, are converted to higher molecular weight compounds that are no longer volatile. More recently, various biotechnological processes, in particular using enzymes, have been used to remove wood extractives or to reduce the VOC content proposed. Enzymatic processes have the advantage over the above-mentioned physico-chemical processes that they are generally much more selective, provide less undesirable by-products and

usually can be carried out under gentler conditions.

A disadvantage of enzymatic processes, however, is that the purified enzymes are expensive to produce and therefore expensive and usually only under certain

Reaction conditions show optimal results. Furthermore, it is disadvantageous in the use of purified enzymes that they usually do not survive their use in an aqueous medium at room temperature or higher temperatures, and therefore reuse is not meaningful. Finally, it has been observed in the enzymes used for VOC reduction that, because of their high substrate specificity, they only lead to the degradation of certain VOC species, while the total VOC content is not sufficiently reduced.

In the biotechnological processes known from the prior art for the removal of wood extractives, certain microorganisms or certain enzymes produced by microorganisms are usually used.

For example, albinotic mutants of sap stain fungi (mainly Ophiostoma spp.) Now commercially available and some white rot fungi have been tested for their ability to degrade lipophilic compounds during storage (Martinez M.

Inigo, et al. , Time course of fungal removal of lipophilic extractives from eucalyptus globulus wood, Journal of Biotechnology 2000, 84, 119-126; MJ Martinez-Inigo, et al. , Biodegradability of extractives in sapwood and heartwood from scots pine by sapstain and white red fungi, Holzforschung 1999, 53 (3), 247-252; TA van Beek, et al. , Fungal biofi-treatment of spruce wood with trametes versicolor for pitch control: Influence on extractive contents, pulping process parameters, Bioresource Technology 2007, 98, 302-311). From DE 10 2006 057 566 AI is a method for

Production of a low-emission raw material known from lignocellulosic particles or their chemical

Main components or contains them as a component. It is an enzymatically catalyzed reaction possibly in

Presence of surfactants carried out; whereby odor and emission-relevant substances of the raw material particles are crosslinked or degraded. Subsequent dehydration of the suspension low-molecular constituents and the enzymes are removed again.

From EP 2 138 528 AI a method for producing a material based on cellulose, in particular of wood and / or a wood material, with a reduced content of wood extract material and / or VOC is known in which the material based on cellulose with a

Oxidation catalyst, in particular with the enzyme laccase, is treated to initiate an autocatalytic oxidation reaction. A disadvantage of using purified enzymes, such as a laccase-mediator system, is that these are usually not only wood extract, but also Oxidize lignin. This is how laccase mediator systems become

for example, for the bleaching of pulp

used. This property of the purified laccase mediator systems can lead to undesirable oxidation reactions when used and the stability of the

affect treated substrates.

The methods hitherto known from the prior art are insufficient in particular for reducing the entire spectrum of VOCs in wood-based materials.

The invention has for its object to provide an effective, inexpensive and sustainable method by which the content of wood extract, precursors of VOC and / or VOC in a material based on

Cellulose, in particular wood and / or a wood material, can be reduced.

This object is achieved by a method for producing a wood-based material according to claim 1, after which a wood-containing intermediate or intermediate product of the wood material is treated with a medium containing microorganisms. The object is further achieved by a wood material according to claim 20, a microorganism-containing medium for reducing the content of wood extract according to

Claim 21, as well as the use of a microorganism-containing medium to reduce the content of

Wood extract, precursors of VOC and / or VOC in wood or a wood-based material according to claim 23. Advantageous embodiments of the invention are specified in the dependent claims and are explained below as the general inventive concept in detail. The inventive method for producing a

Wood material is characterized in that a wood-containing intermediate or intermediate product of the wood material is treated with a medium containing microorganisms. The term "microorganism" in the sense of the invention means any kind of microscopically small animal. Microscopically small means that the individual is no longer visible to the naked eye. This is usually the case for individuals with diameters of 100 μηα and smaller. The term "microorganism" as used herein includes both procaryotic and eukaryotic animals and, in addition to unicellular organisms such as bacteria, yeasts, flagellates or ciliates, also multicellular organisms such as e.g. Rotifers. To microorganisms in the sense of

The invention includes, in particular, those selected from the group consisting of bacteria, archaea, fungi, microalgae and protozoa.

When referring to "microorganisms" in the plural, it is a plurality (at least two) of

meant different types of microorganisms and not just a plurality of individuals of a microorganism species. The term "wood material" according to the invention understood a variety of materials that consist of wood or wood. Examples of wood-based materials in the sense the invention are wood panels or wood moldings, which may be both composite materials of individual wood particles as well as materials made of solid wood. Particularly good results are found in the invention

Procedure when the wood material is a

Wood composite material is obtained by comminution of

Cellulose-containing materials and / or subsequent assembly of the structural elements is generated. Such

Structural elements can be any size reduction products of cellulose-containing materials, such as

Wood particles, in particular wood chips, wood strands, wood fibers and / or wood veneers. Wood-based materials in the sense of this ·

Invention are in particular those based on solid wood,

Veneer materials, chipboard materials, fiber materials or other composite materials. This is suitable

inventive method particularly well for the production of pressed wood materials, especially of fiber or OSB boards. Depending on the wood material, the wood containing pre- or

Intermediate, which is treated in the process according to the invention with a medium containing microorganisms, be different. Is the wood material through

Crushing of cellulose-containing materials and subsequent assembly of the structural elements generated, the precursor or intermediate may be selected, for example, from 1.) the cellulose-containing starting material; 2.) the structural elements obtained by comminution, such as the wood particles, wood chips, wood strands, wood fibers or wood veneers and 3.) almost finished

Wood material. In principle, the higher the reaction rate of the process according to the invention

Surface of the treated or intermediate product of the wood material is. The surface is known to increase with decreasing particle size. Thus, in the

inventive method a higher

Reaction speed achieved when the treated precursor or intermediates of the wood material has a small particle size.

Particularly good results are obtained when the pre- or intermediate products of the wood material to be treated, wood particles (especially wood chips, wood strands or

Wood fibers) whose maximum diameter is 2 cm or smaller, preferably 1.5 cm or smaller.

In contrast to the known methods that is

However, the method according to the invention is not limited to using small-sized materials, such as chips, strands or fibers, as substrates. Rather, it may be sufficient to treat only the surface or only part of the surface of the material to be treated with a microorganism-containing medium to effect a reduction of the VOC or VOC precursors for the entire material.

Thus, for the purposes of this invention, the surface of an almost finished wood material, such as a pressed chipboard, fiber or OSB board, treated with a medium containing microorganisms, so that the

effect of reducing VOC emissions in the final product according to the invention. Surprisingly, it was found that the content of

Wood extract, precursors of VOC and / or VOC in materials based on cellulose, such as wood or a wood material, particularly simple and

cost-effective manner can be reduced if that

Material based on cellulose or a pre-or

Intermediate thereof is treated with a medium containing microorganisms.

It was found that the most diverse

Media containing microorganisms can effect the inventive effect of reducing VOC emissions in the final product.

A particular advantage of the method according to the invention is that by treatment with a

Microorganism-containing medium not only selectively reduces individual VOC species, but the total VOC content over the entire VOC spectrum can be reduced. Without wishing to be bound by scientific theories, this effect appears to be due to the complex interplay of the various microorganism species present in the

Microorganism-containing medium.

With the method according to the invention, the

different metabolic activities of different microorganisms used in synergy. In this case, substances that an individual organism alone can not metabolize, be implemented in cooperation of different acting microorganisms ideally to water and carbon dioxide. According to a preferred embodiment, the medium according to the invention contains a multiplicity of different ones

Microorganism species, so at least two

Microorganism species, preferably at least 10, at least 100, at least 250 or at least 500 different

Microorganism species. It has been observed that the highest possible biodiversity in the microorganism-containing medium leads to a particularly high performance in terms of the VOC reduction. In particular, the richness of species extends the spectrum of VOC species and corresponding VOC precursors, which is characterized by the

inventive method can be reduced.

A variety of different microorganisms that live together in a medium or habitat, found in nature often in the form of so-called microbiocenoses. According to a preferred embodiment of the invention, the contents contained in the medium according to the invention are derived

Microorganisms from a microbiocenosis or represent a microbiocenosis.

A microbiocenosis is understood by the person skilled in the art

Consortium of microorganisms or a

Microorganism community, which represents the totality of microorganisms occurring in a microhabitat.

Microbiocenoses represent a dynamic system that is constantly changing and constantly evolving in the environment and environment

Adjusts nutrient conditions. Stay individuals and

Species numbers constant over a longer period of time, it is said that the microbiocenosis is in balance. Constant change of composition

Microorganisms and the adaptability of It is also believed that ikrobioenoses generally explain why it has been found that a variety of naturally occurring microbiocenoses can be successfully used in the method of the present invention. This is true even in the event that the microbiocenoses are not affected by their

original natural environment to the metabolism of wood extractives, VOC precursors or VOC were used. In such cases, a rapid adaptation of the microbiocenosis to the preliminary or intermediate products of the wood-based material to be treated as a new nutrient source presumably leads to the observed reduction of the invention

Content of wood extract, precursors of VOC and / or VOC. The success of the microorganism-containing medium used according to the invention is presumably based on the fact that the

Nutrient claims and metabolic pathways of the individual types of microorganisms contained therein are very different and thus, for example, the metabolite of one microorganism, the substrate for another

Can represent microorganism. This is possible

probably explain why the process according to the invention can reduce the total content of VOC over the entire VOC spectrum and not only selectively reduce individual VOC species.

The medium to be used according to the invention can be

Planktonically (ie, like plankton floating in water), flocculated (ie, as clumping of smaller groups of microorganisms), or contained in the form of an intact or comminuted biofilm. If this is talk about medium, so it is with each

Liquid meant in which the microorganisms used can survive. According to a preferred embodiment, a liquid is selected as the medium in which the

used microorganisms multiply and / or

can be metabolically active. Preferably that is

Microorganism-containing medium is a water-based medium, i. the proportion of water in the liquid phase is at least 50% by weight, preferably at least 80% by weight and especially preferably at least 90% by weight or

at least 95 wt .-% based on the total weight of the liquid components of the medium. According to a further embodiment of the invention, water is used as the medium

used, in which the microorganisms are introduced. The microorganism-containing medium may also be a microorganism culture or a dilution thereof.

According to a further embodiment of the invention, the substances contained in the medium according to the invention are derived

Microorganisms from a biofilm. Under a biofilm the skilled person understands a special form of a

Microbiocenosis in which the various

Microorganism species, optionally together with other particulate matter such. Sand, on a surface or

Attached to the interface. Biofilms usually contain one

Schleimmatrix from extracellular polymeric substances (EPS), in which the cells are immobilized. The prerequisites for the formation of biofilms - namely the

Coincidence of microorganisms, interfaces,

Nutrients and moisture - are given almost everywhere. Biofilms provide protection and protection for microorganisms

Habitat, a symbiotic coexistence favored of various species. Favorable to a planktonic lifestyle (as an individual organism free

floating or floating) is in biofilms especially the protection against adverse environmental influences, such as dehydration, extreme pH levels or chemicals and

Disinfectants. At least in lower lying

Layers of biofilm living microorganisms are protected from such environmental influences. This probably also explains why the most diverse types of microorganisms can develop optimally in the shelter of a biofilm. This particular biodiversity is especially due to the presence of ecological

Niches in the biofilm (e.g., flow dead zones or

Oxygen-free zones in the deeper layers of the biofilm) further supported. In addition, the EPS matrix also acts as a nutrient storage for bad times.

Biofilms which contain microorganisms which are particularly suitable for the process according to the invention are widespread. For example, suitable biofilms are formed at the

Surface and at the wall and bottom surfaces of standing water, such as in waste water tanks or

Rainwater catchment basin. Preference according to the invention is biofilms derived from waste water, biological wastewater treatment or plants of the wood and / or woodworking industry and / or biofilms that already with wood and / or

Wood components have come into contact. Preferred wastewater types in which biofilms with microorganisms suitable for the method according to the invention are present are wastewater types from the wood-based material production, in particular Waste water resulting from the treatment of wood by steaming, cooking, defibering or drying.

For example, as wastewater from the

HolzwerkstoffProduktion Stopfschneckenaustragswasser a

Sägespan Refiners or a wood chip refiner can be used. A refiner serves to shred wood chips or sawdust. The StopfSchnecke is the refiner

upstream and used for drainage and supply to the refiner. The chips or sawdust are cooked in front of the refiner to soften the material. The

excess water including the extracted

Holzbegleitstoffe is then separated in the StopfSchnecke before the refiner, which is then available for this application. The Stopfschneckenaustragswasser is due to the conditions prevailing in the digester (up to 8 bar pressure and 160 ° C) initially almost sterile, but learns in the downstream collection tank after cooling a

Colonization by microorganisms.

Treated by the method according to the invention

Materials based on cellulose, such as the wood-containing precursors or intermediates of a

Wood material, have a reduced content

Wood extract, precursors of VOC and / or VOC. In particular, the process of the invention makes it possible to effectively reduce the content of unsaturated compounds in the wood extract such as, for example

unsaturated fatty acids or unsaturated fatty acid esters, eg linoleic acid or triglycerides with at least one unsaturated fatty acid constituent. Since these compounds VOC precursors for the VOC class of aldehydes represent, can be reduced particularly effective with the inventive method aldehyde emissions.

The term wood extract according to the invention one or more wood ingredients understood that can be extracted from the wood with polar and / or apolar organic solvents and / or water, for example with water, alcohol, benzene, hexane, cyclohexane, ether and / or acetone ,

As already discussed, in addition to the already existing VOCs, the VOC precursor compounds contained in the wood extract substance form additional VOC species when heated.

Presumably due to the reduced content

Wood extract material and VOC precursor compounds is characterized by the method according to the invention treated intermediate or intermediate product of a wood material also characterized in that when heated, for example in a

Drying step, a lower amount of VOC is released. The same applies to the end product, the wood-based material, which also has lower VOC emissions.

VOCs whose content is to be reduced by the process according to the invention are, for example, aromatic

Hydrocarbons, aliphatic hydrocarbons, terpenes, aliphatic alcohols, aromatic alcohols, glycols,

Glycol ethers, glycol esters, aldehydes, ketones, organic

Acids, esters and lactones. The VOCs whose content is to be reduced by the method according to the invention also include, for example

aromatic hydrocarbons, such as toluene, Ethylbenzene, o-, m- and p-xylene, isopropylbenzene, n-propylbenzene, 1-propenylbenzene, 1, 3, 5-trimethylbenzene, 1,3,5-trimethylbenzene, 1, 2, 3-trimethylbenzene, 2-ethyltoluene, 1-isopropyl-2-methylbenzene (o-cymene), 1-isopropyl-3-methylbenzene (m-cymene), 1-isopropyl-4-methylbenzene (p-cymene), 1,2,4,5-tetramethylbenzene, 1 , 2,4,5-tetramethylbenzene,

1, 2, 5-tetramethylbenzene, 1, 4-diisopropylbenzene, 1,4-diisopropylbenzene, 1-phenyldecane and isomers, 1-phenylundecane and isomers, 4-phenylcyclohexene (4-PCH), styrene,

Phenylacetylene, 2-phenylpropene (α-methylstyrene), vinyltoluene (all isomers: o-, m-, p-methylstyrenes), alkylbenzenes, naphthalene or indene.

Furthermore, of the VOCs whose content is with the

inventive method to be reduced,

For example, aliphatic hydrocarbons, such as 3-methylpentane, n-hexane, cyclohexane,

Methylcyclohexane, n-heptane, as well as other saturated ones

aliphatic hydrocarbons having 6 to 8 or 9 to 16 carbon atoms.

An important subgroup of VOCs whose content is to be reduced by the process according to the invention are, for example, terpenes, for example 3-carene, α-pinene, β-pinene, limonene and other terpenes.

The VOCs whose content is to be reduced by the process according to the invention include, for example, furthermore aliphatic alcohols, such as, for example, ethanol, 1-propanol, 2-propanol, tert-butanol, 2-methyl-2-propanol, 2-methyl- 1-butanol, 1-butanol, pentanol (all isomers), 1-hexanol, cyclohexanol, 2-ethyl-1-hexanol, 1-octanol, 4-hydroxy-4- methyl-pentane-2-one (diacetone alcohol), other C4-C10 saturated n- and iso-alcohols, other C11-C13 saturated n- or iso-alcohols and aromatic alcohols, such as

for example, phenol, BHT (2,6-di-tert-butyl-4-methylphenol), benzyl alcohol.

Another subgroup of VOCs whose content is to be reduced by the process according to the invention are, for example, glycols, glycol ethers and glycol esters, for example propylene glycol (1,2-dihydroxypropane), ethylene glycol (ethanediol), ethylene glycol monobutyl ether, diethylene glycol, diethylene glycol monobutyl ether, 2-phenoxyethanol,

Ethylene carbonate, 1-methoxy-2-propanol, 2, 2, 4-trimethyl-1,3-pentanediol monoisobutyrate (Texanol®), butyl glycolate (hydroxyacetic acid butyl ester), butyl diglycol acetate (ethanol, 2- (2-butoxyethoxy) acetate, BDGA),

Dipropylene glycol monomethyl ether, 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, 2-methylethoxyethanol, 2-hexoxyethanol, 1, 2-dimethoxyethane, 1, 2-diethoxyethane, 2-methoxyethyl acetate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, 2- (2 Hexoxyethoxy) ethanol, 1-methoxy-2- (2-methoxyethoxy) ethane, 2-methoxy-1-propanol, 2-methoxy-1-propyl acetate,

Propylene glycol diacetate, dipropylene glycol,

Dipropylene glycol monomethyl ether acetate, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether,

Dipropylene glycol mono-t-butyl ether, 1, 4-butanediol,

Tripropylene glycol monomethyl ether,

Triethylene glycol dimethyl ether, 1, 2

Propylene glycol dimethyl ether, TXIB, ethyl diglycol,

Dipropylene glycol dimethyl ether, propylene carbonate,

Hexylene glycol (2-methyl-2,4-pentanediol), 3-ethoxy-1-butanol,

1, 2-propylene glycol n-propyl ether, 1, 2-propylene glycol butyl ether, diethylene glycol phenyl ether and neopentyl glycol (2, 2-dimethylpropane-l, 3-diol).

Furthermore, of the VOCs whose content is with the

inventive method to be reduced,

for example, aldehydes, such as butanal,

Pentanal, hexanal, heptanal, octanal, nonanal, decanal, 2-butenal (crotonaldehyde, cistrans mixture), 2-pentenal, 2-hexenal, 2-heptenal, 2-octenal, 2-nonenal, 2-decenal, 2-undecenal , Furfural, glutaraldehyde, benzaldehyde, acetaldehyde or propanal, as well as ketones, such as

Ethyl methyl ketone, 3-methyl-2-butanone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, 2-methylcyclopentanone, 2-methylcyclohexanone, acetophenone, 1-hydroxyacetone (1-hydroxy-2-propanone) or acetone.

Another subgroup of VOCs whose content is to be reduced by the process according to the invention are organic acids, such as, for example, acetic acid,

Propionic acid, isobutyric acid, butyric acid, pivalic acid, n-valeric acid, n-caproic acid, n-heptanoic acid, n-octanoic acid or 2-ethylhexanoic acid.

Examples of esters and lactones which belong to the VOCs whose content is to be reduced by the process according to the invention are, for example, methyl acetate, ethyl acetate, vinyl acetate, isopropyl acetate, propyl acetate, 2-methoxy-1-methylethyl acetate, n-butyl formate, methyl methacrylates,

Isobutyl acetate, 1-butyl acetate, 2-ethylhexyl acetate,

Methyl acrylate, ethyl acrylate, n-butyl acrylate, 2-

Ethylhexyl acrylate, acrylic acid ester, dimethyl adipate, dibutyl fumarate, dimethyl succinate, Dimethyl glutarate, hexanediol diacrylate,

Dibutyl maleate, butyrolactone,

Glutaric diisobutyl ester, diisobutyl succinate. Furthermore, the following compounds also belong to the VOCs whose content is to be reduced by the process according to the invention: for example 1,4-dioxane, caprolactam, N-methyl-2-pyrrolidone, octamethylcyclotetrasiloxane, methenamine,

Hexamethylenetetramine (formaldehyde releaser), 2-butanone oxime, tributyl phosphate, triethyl phosphate, 5-chloro-2-methyl-

4-isothiazolin-3-one (CIT), 2-methyl-4-isothiazolin-3-one (MIT), riethylamine, decamethylcyclopentasiloxane,

Dodecamethylcyclohexasiloxane, tetrahydrofuran and

Dimethylformamide.

The process of the invention has proven to be particularly effective in reducing the content of VOCs

Aldehyde class and precursors of aldehyde emissions (fatty acids) proved.

The inventive method for producing a

Wood-based material involves the step of making a wood

containing intermediate or intermediate product of the wood material is treated with a medium containing microorganisms.

When it comes to "treatment", it means an active action. In particular, this is the in

Bringing the wood-containing or- or

Intermediate with the microorganism-containing medium and possibly a subsequent incubation meant. Not covered by the term "treatment" as used herein are processes in which microorganisms have already been used present on or in the wood containing precursors or intermediates of wood-based material were present, act on these over time and begin to decompose it (for example, during storage, processing or composting). The term "treatment" as used herein necessarily includes the step of microorganisms containing the wood-containing precursor or intermediate product of the wood

Wood material are actively supplied, or brought into contact with this.

According to a preferred embodiment of the invention, the wood-containing precursor or intermediate product of

Wood material treated by being wetted with the microorganism-containing medium. Preferably, the wetted precursor or intermediate product of the wood material

then incubated.

Under "wetting" within the meaning of the invention, each in

Bringing the pre-or wood-containing contact

Intermediate containing a microorganism

Medium understood, in particular the application of this medium to the surface of the pre- or intermediate product. It has proved to be particularly advantageous if the ratio of liquid (microorganism-containing medium) to the pre- or intermediate product is such that the pre- or

Intermediate product is not floating in the medium or suspended, but is only moistened by this. This condition is usually fulfilled when the

Total moisture content of the wood, that is to say including the medium used for wetting, is at most about 300%, preferably at most about 250% and particularly preferably from about 130% to about 250%. The Surface of the wood-containing intermediate or precursor may be completely or partially wetted with medium containing microorganisms.

According to a preferred embodiment of the invention, the wood-containing precursor or intermediate of the

Wood material in the treatment with the microorganism-containing medium has a moisture content of at most about 300%, preferably at most about 250% and more preferably from about 130% to about 250%, on. It has been found that with these wood moistures optimum results in terms of VOC reduction and the mechanical-chemical properties of the produced

Wood materials result. Where "wood moisture" means

According to the invention, the moisture content of the wood, i. the

Ratio of the wood contained in the wood and possibly the wood

surrounding amount of water to the wood dry weight (Darrgewicht) of the wood in weight percent. According to the invention, the wood moisture can be calculated in accordance with DIN EN 322 using the following formula: wood moisture (%) = 100 × (wet weight - Darr weight) / Darr weight. Darrgewicht as used here means the weight after drying at a

Temperature from 103 ° C ± 2 ° C to constant mass, as described in DIN EN 322. Since the inventive method already with low

Moisture during treatment with the medium containing microorganisms provides very good results, it is possible to significantly reduce water consumption and drying energy consumption in production. This is in view of the rising energy costs of Advantage and meets the requirements for a sustainable and environmentally friendly production.

Basically, the person skilled in various ways for wetting and / or setting the desired moisture content of wood are known. Wetting by spraying, spraying, spraying and / or misting has proved to be particularly practical for the process according to the invention. It is also

conceivable that the wood-containing precursor or intermediate, for example, in a liquid bath, which with the

Microorganisms containing medium is immersed, dipped and then removed again to effect wetting. A soaking or flooding the wood-containing intermediate or intermediate product is conceivable.

Preferably, the treatment includes the pre- or

Intermediate product of the wood material with the medium containing microorganisms also an incubation step. The mixture of wood-containing intermediate or intermediate product and microorganism-containing medium is preferably incubated at about 15 ° C to about 70 ° C. According to a preferred

Embodiment of the method according to the invention, the incubation at about 15 ° C to about 60 ° C, preferably at about 15 ° C to about 50 ° C and in particular at about 15 ° C to about 40 ° C. There are thus no precautions for temperature control during incubation required and this can

especially at room temperature. Accordingly, if the produced wood material is a pressed wood material, such as a fiber or OSB board, the incubation and / or treatment step may be in a conventional wet chip bunker prior to drying or before the digester. Since the treatment according to the invention with the microorganism-containing medium already at low temperatures - and especially at room temperature - gives very good results, it is possible to reduce energy consumption in the

Significantly reduce wood-based material production. This is advantageous with regard to the process economy and the energy efficiency of the method according to the invention. The

Wood particles, for example, after being in contact with the microorganism-containing medium, can simply be left in the apparatus used for application of the medium to be incubated there at room temperature. Experiments have shown that the inventive method in all, depending on the geographical location and

Season, prevailing ambient temperatures, in particular between about 15 ° C and about 40 ° C, gives very good results.

Regarding the preferred incubation period for the

Treatment with the microorganism-containing medium will give optimum results when the treatment or incubation is for at least about 180 minutes. From this treatment or incubation period arises

sufficient reduction in wood extract content, precursors of VOC and / or VOC. A longer incubation period is usually advantageous. Depending on

Activity of the microorganism-containing medium, the nature of the wood-containing pre- or

Intermediate and its content of wood extract, precursors of VOC and / or VOC, for example, a treatment or incubation period of 72 hours or more is conceivable. For many applications it has been shown that the

Microorganism-containing medium must not have a particular pH or special buffer system for use in the method according to the invention. Consequently, a further advantage of the method according to the invention is the fact that many times good results can be achieved without having to set or monitor a specific pH.

Nonetheless, optimum results are obtained when treatment with the microorganism-containing medium occurs at a pH of about 4 to about 6.

In practice, it has also proved to be advantageous if the mixture of wood-containing pre- or

Intermediate and microorganisms containing medium to

Beginning and / or is mechanically mixed during the treatment in order to obtain a uniform distribution of the

Microorganisms on the wood containing pre- or

To ensure intermediate product. For mixing can

For example, a plowshare mixer can be used. However, the person skilled in the art is also dependent on the quantity and size of the wood-containing intermediate or intermediate product

suitable mixing equipment known. Practical experiments have shown that for most applications, mixing for about 1 to about 10 minutes, especially for about 5

Minutes is sufficient to achieve optimal results.

With the process control according to the invention it is possible to carry out the VOC reduction at normal pressure and without applying a vacuum. Practical experiments have also shown that it is for

Not carrying out the method according to the invention

is required, air and / or oxygen during the

Treatment in the reaction mixture. Also, neither stirring nor shaking the mixture of wood

containing pre- or intermediate product and microorganisms containing medium during the treatment needed.

However, it may lead to an acceleration of the method according to the invention, when the treatment under aerobic

Conditions, i. is carried out in the presence of oxygen or if air and / or oxygen during the

Treatment is introduced into the mixture of wood-containing intermediate or intermediate product and medium containing microorganisms. This applies in particular when the microorganisms contained in the medium according to the invention also comprise aerobic microorganisms. According to a preferred embodiment of the invention, when in the

According to the invention contained microorganisms, each based on the total amount of microorganisms

Individual organisms, containing at least about 50 wt .-%, in particular at least about 70 wt .-% or at least about 90 wt .-% aerobic microorganisms, the inventive

Treatment of wood-containing intermediate or precursor carried out in the presence of air and / or oxygen. In this case, it is advantageous if during the

Treatment is carried out aeration and / or introduction of air and / or oxygen in the mixture of wood-containing intermediate or intermediate product and microorganism-containing medium. According to another possible embodiment of the invention, during the treatment with the microorganisms

containing medium alternating aerobic and anaerobic

Conditions set to the diversity of

metabolizing precursors of VOC and / or VOC and the claims of the heterogeneous natural

Microbial populations.

According to a preferred embodiment of the invention, those contained in the medium according to the invention

Microorganisms have been recovered from wastewater and / or filter residues from the treatment of this wastewater. The

In particular, microorganism-containing medium may also contain or consist of wastewater and / or filter residues from the treatment of this wastewater. According to a further embodiment, the

Filter residues from the treatment of the waste water to live filter residues. Surprisingly, it has been shown that it is not necessary for the reduction of wood extract, precursors of VOC and / or VOC, especially selected

Add microorganisms to the material to be treated, but that it is sufficient, the wood-containing precursor or intermediate with naturally occurring microbiocenoses, biofilms or even with a "waste product", namely the above

designated wastewater and / or live filter residues from the treatment of wastewater to treat. In particular, wastewater and / or filter residues from the

Waste water treatment seems to be due to the very wide range of impurities found in wastewater a microbiocenosis, which contains in principle all microorganisms required for the degradation of wood extract, precursors of VOC and / or VOC. In common sewage and / or animated filter residues from the

Treatment of wastewater seems so special

Microorganisms capable of degrading or co-metabolizing wood extract, precursors of VOC and / or VOC. Consequently, the microorganisms necessary for VOC reduction are in common

Wastewater types and / or animated filter residues from the treatment of wastewater already in suitable

Microbiocenoses and nutrients.

The inventive method is especially from

ecological point of view, since it offers a possibility to reuse wastewater and waste (in the form of filter residues) and thus to recycle it. The result

Saved disposal and landfill costs make the inventive method overall also economical

attractive.

When referring to "sewage", it is meant to mean any water that is contaminated by use or drained from paved surfaces that is seized and / or discharged. This definition corresponds to that in German

Wasserhaushaltsgesetz (WHG v. 31 July 2009, BGBl. I p. 2585) used the definition. "Sewage" as used here

means that by domestic, commercial,

agricultural or other use in his

Properties changed water and the water draining together in dry weather (dirty water) as well as precipitation from the area of built-up or paved areas collected effluent water

(Rainwater). Those emanating from and collected from facilities for treating, storing and depositing waste

Liquids are also considered as waste and thus as wastewater.

The term "wastewater" as used herein means in

Based on the German Drinking Water Ordinance (TrinkwV BGBl I 2001 p. 959 ff.), In particular a liquid that no longer meets the requirements for drinking water in relation to the total germ count. The total germ count is a non-specific size, which is described by a in the TrinkwV

microbiological examination can be determined. It indicates how many colonies of microorganisms accumulate on an agar medium normalized for this purpose over the course of 48

Make hours at 22 or 36 ° C, if you distribute 1 ml of water sample on or in the nutrient medium.

Of the total germ count determined according to TrinkwV, not all microorganisms contained in the water are detected. This is basically impossible if the habitat - as usual - a microbiozoanosis with a wide

Spectrum of physiologically diverse microorganisms contains. There are no culture conditions

(Composition of the medium, incubation temperature and - atmosphere), among which all in a natural

Habitat microorganisms can proliferate optimally. Nevertheless, the according to TrinkwV certain

Total germ count is a good indicator of the actual total germ count. According to the German Drinking Water Ordinance, a limit value of 100 cfu / ml ("colony-forming units per milliliter") for tap-fed drinking water from wells and of 1000 cfu / ml for temporarily stored in tanks drinking water.

Thus, if "wastewater" is mentioned here, this refers in particular to a fluid which has a total bacterial count determined according to TrinkwV of more than about 1000 CFU / ml, in particular more than about 2000, preferably more than about 3000, more than about 5000 or more than about 10,000 cfu / ml.

According to a particular embodiment of the invention, the wastewater is selected from the group consisting of

Rainwater, domestic sewage, municipal

Wastewater, industrial wastewater, wastewater from

Water treatment plants and combinations thereof.

Practical experiments have shown that the inventive method works particularly well when the wastewater

Wastewater is that with wood and / or wood components in

Touch has come. Examples of such wastewater are

Wastewater from the wood and / or woodworking industry.

The wastewater can, for example, from the

HolzwerkstoffProduktion, in particular from the treatment of wood by steaming, cooking, defibering or drying come.

The teaching of the invention may according to another

Embodiment of the invention are also realized in that the microorganisms contained in the medium biofiimals from sewage treatment plants and / or living substances in Form of activated sludge from sewage treatment plants or wastewater from a woodchip biofilter a sewage treatment plant were obtained. The microorganism-containing medium can

In particular, biofilms from sewage treatment plants and / or living substances in the form of activated sludge from sewage treatment plants or wastewater from a woodchip biofilter contain a sewage treatment plant or consist of these.

When using microorganisms from biofilms and / or living substances in the form of activated sludge from sewage treatment plants, it has proven to be particularly practical if the activated sludge from sewage treatment plants is selected from the group consisting of aerobic or anaerobic sludge

Treatment tank, excess sludge of the aerobic or anaerobic treatment tank, sludge from the digester, primary sludge and combinations thereof.

In addition to the use of activated sludges from municipal

Wastewater treatment plants are also activated sludge from industrial

Sewage treatment plants usable, which are usually free from pathogenic germs and therefore hygienically safe.

Basically, the inventive method works with a variety of different microorganisms and in particular with those that are not already on the

Metabolism of cellulosic materials, such as wood, are used. This is especially true in the case where the microorganisms are from a microbiocenosis, such as a biofilm. As explained above, microbiocenoses are characterized by a very high adaptability to new nutrient conditions. In practice, it has been found that when using microorganisms that are not already used to the metabolism of cellulose-containing materials such as wood, a "settling phase" (lag-phase) of the

Systems is observed. In this acclimation phase initially only a slow degradation of

Wood extract, precursors of VOC and / or VOC. In a kind of "learning process", following the "acclimatization phase", adaptation and selection significantly increase the degradation of wood extract material.

Precursors of VOC and / or VOC (log-phase).

The occurrence of the described acclimation phase (lag phase) can be avoided or reduced if the

Microorganism-containing medium before its use in the inventive method in a bioreactor on material based on cellulose and / or the metabolism of wood extracts, precursors of VOC and / or VOC was adapted. In this case, the cellulose-based material may in particular be identical to the preliminary or intermediate product of the wood-based material to be treated and containing the wood described above.

Such a pre-adaptation to the metabolism of

Wood extractives, precursors of VOC and / or VOC result in an acceleration of the process and a further improvement in VOC reduction over the entire range of VOC species. This is probably due to the fact that the pre-adapted microorganisms could already change their metabolism accordingly, or such microorganisms could preferentially multiply, which also or particularly good wood extract, Be able to metabolize precursor substances of VOC and / or VOC.

The pre-adaptation can be carried out, for example, by containing those contained in the medium according to the invention

Microorganisms are first cultivated and thereby common wastewater types of the wood-based industry, in particular

Wastewater from the treatment of wood by steaming, cooking, defibering or drying, comes (for example

Dump auger discharge water, water from the discharge auger of the MDF digester, water from the rainwater retention basin,

Sewage of the trunk washing, etc.) are added to the cultivation approach. The aim is to get the microorganisms already accustomed to wood-relevant ingredients. This results firstly in the selection (preferential accumulation) of suitable microorganisms and secondly in the formation and induction of suitable enzyme systems in the microorganisms which can metabolize wood extract, precursors of VOC and / or VOC.

According to a particular embodiment of the invention, the microorganisms are recovered after and / or during the implementation of the method according to the invention, and

further cultivated. The microorganisms thus obtained can be reused in a further application of the method according to the invention. As a result of this, a specially adapted microbiocenosis can form over several applications of the process according to the invention, optimally adapted to the metabolization of wood extract substance,

Precursors of VOC and / or VOC is set. In principle, various sources are known to those skilled in the art

Microorganisms and in particular microbiocenoses and

Biofilms that are suitable in the invention

Method to be used, known. For many

In applications, it is particularly advantageous if the microorganisms contained in the medium are quantitatively (based on the total number of microorganisms Einzellebewesen) to at least about 50%, preferably at least about 80% and more preferably at least about 90% bacteria. This is the case in most natural microorganism populations, such as those in wastewater and / or live

Filter residues from the treatment of wastewater

happen, the case. Yeasts have proven unsuitable for many applications. Accordingly, one embodiment of the invention provides that the microorganisms contained in the medium according to the invention consist quantitatively (based on the total number of microorganisms Einzellebewesen) at most about 20%, preferably at most about 5% and more preferably at most about 1% of yeasts.

It has proved to be particularly advantageous if the medium containing microorganisms at least. one

Containing bacterial strain selected from the group consisting of Enterobacteriacea, in particular Enterobacter chloacae, Klebsiella sp. , Serratia ficaria, Pantoea sp. , Pseudomonadacea, in particular Pseudomonas sp. and

Bacillus sp.

Practical experiments have shown that optimal

Set results when the medium according to the invention the Microorganisms in a number of at least 10 ⁴ microorganisms / ml, preferably at least 10 ⁵

Microorganisms / ml and more preferably at least 10 ⁶

Contains microorganisms / ml.

In this case, the number of microorganisms / ml can be determined by counting the microorganisms present in a sample (single organisms) in a Thoma counting chamber. Such

Counting chamber is known in the art and serves the

light microscopic counting of all kinds of small ones

Particles that are in a particle suspension.

Counting chambers are particularly used for the quantification of cells and microorganisms in medicine and biology. Are the microorganisms in the medium

flocculates, that is, as a clumping of smaller groups of microorganisms, or in the form of an intact or

crushed biofilm before, should the sample before the

Counting briefly gevortext or sonified to obtain a separation into individuals.

Depending on the type of microorganisms to be counted, a certain number of large or group squares of the thoma chamber is then counted and an average value is formed from this. Multiplying this value by a corresponding factor (reciprocal of the product of square area and chamber height) gives the number of microorganisms per unit volume.

The following evaluation formula is used:

Particles per μΐ volume = counted particles / (counted area (mm ² ) · chamber depth (mm) · dilution). If the total bacterial count according to TrinkwV is used as a yardstick (see above), the medium according to the invention preferably contains the microorganisms in a total microbial count of at least about 10 ³ CFU / ml or at least about 10 ⁴ CFU / ml, preferably at least about 10 ⁵ CFU / ml and more preferably at least about 10 ⁶ cfu / ml. With such high

Germ numbers must be described in the TrinkwV

a correspondingly high dilution can be used microbiological üntersuchungsverfahren so that individual colonies can be distinguished on the agar medium. The selected dilution factor can then be extrapolated back to the total bacterial count in CFU / ml.

It has also proven to be special in field trials

proven advantageous when treated with the

Microorganisms containing medium

Microorganism density of at least about 1 x 10 ³ ,

preferably at least about 1 x 10 ⁴ , more preferably at least about 1 x 10 ^5, or at least about 1 x 10 ⁶

Microorganisms individuals per g of the wood-containing intermediate or intermediate product is present. As special

has become practical in the treatment with the

Microorganisms containing medium

Microorganism density of about 1 x 10 ³ to about 1 x 10 ¹² , in particular from about 1 x 10 ⁵ to about 1 x 10 10 ⁱ⁰

Microorganisms individuals per g of wood-containing intermediate or precursor exposed. The

Microorganism density can be calculated by first counting the number of microorganisms / ml of the microorganism-containing medium as described above. Subsequently, the number of microorganisms can be determined by the wood moisture prevailing during the treatment Individuals per g of the wood-containing fore or aft

Intermediate can be calculated. Just as the wood moisture described above is also the microorganism density based on the dry weight of wood (Darrgewicht).

According to a further embodiment of the invention, the microorganism-containing medium may be selected

metabolism-stimulating additives are added. Such additives are those skilled in the use of

Microbiocenoses and biofilms in the biological

Wastewater treatment known. Examples of suitable

Additives that stimulate microbial biomass include vitamins, glucose, and nitrogen

Nutrients that ensure a sufficient nitrogen supply of microorganisms. It has been found that the addition of such additives can decisively influence the degradation efficiency with respect to VOCs and their precursors.

Furthermore, additional, possibly purified,

Microorganisms and their exoenzymes (eg lignin degrading

Fungi and their enzyme spectra) are deliberately introduced into the microorganism-containing medium.

The inventive method for producing a

Wood-based material serves in particular to produce a wood material with a reduced content of wood extract,

To produce precursors of VOC and / or VOC. The achievable with the process according to the invention reduction of the content of wood extract, precursors of VOC and / or VOC is believed to be due to biochemical processes of the primary and secondary metabolism in the

According to the invention contained microorganisms. In practice, optimal results can be achieved with the method according to the invention if the wood material is a pressed wood material, in particular a fiber or OSB board.

When referring to "pressed wood material", it refers to all wood-based materials whose production comprises at least one step in which wood particles are compacted using pressure

"Wood material" means any material or article containing or consisting predominantly of wood or wood-like materials. The term "woody materials" as used herein includes all lignocellulosic materials. Examples of woody

Materials within the meaning of this invention are straw, hemp and / or flax.

According to a particular embodiment of the invention, wood particles are used as a wood-containing intermediate or intermediate product and the above-described method for producing the wood-based material is designed such that it

including at least the following steps: a) contacting wood particles with the

Microorganism-containing medium;

b) incubation of the material from step a);

c) drying the pretreated wood particles at 80 to

400 ° C;

d) Beieimen the pretreated wood particles with a

Binder; and e) pressing the mixture into a pressed one

Wood material.

By "wood particles" is meant any article which is predominantly of wood or contains woody material and which is suitable for the production of a wood material by compression.For the purposes of the invention, wood particles are understood in particular to be any form of fragments obtained by crushing cellulose Materials are wood particles within the meaning of this invention

in particular any form of small-sized wood material, i. especially shavings, OSB strands, fibers and / or flour. According to a preferred embodiment, the wood particles, especially if they are chips, fibers or strands, consist predominantly or completely of native wood.

The steps a) and b) are the above

described treatment of wood according to the invention

containing intermediate or intermediate product with a

In this respect, the above applies to the embodiments of this treatment,

in particular on possible forms of contact and incubation, In step c), the drying of the pretreated

Wood particles at a temperature of about 80 ° C to about 400 ° C, preferably from about 150 ° C to about 350 ° C and more preferably from about 150 ° C to about 250 ° C instead. Drying in the latter temperature range has proven to be particularly effective. When we speak of drying or drying, it means heating the treated wood particles at a certain temperature (ambient temperature). The skilled person is known or he can by simple

Try to find out what residual moisture of the treated wood particles after drying for a particular

Wood particles - binder combination is most suitable. As has been found to be particularly useful if in step c) of the process according to the invention, the heating of the

Wood particles takes place until the wood particles have reached a residual moisture content of 0.1 to 10%, in particular from 0.5 to 6%, preferably from 1 to 3%.

The amount of the binder used in step d) of the process according to the invention is preferably from 0.01 to 15% by weight, in particular from 0.1 to 10% by weight, more preferably from 0.5 to 7.5% by weight, based on the dry weight of the wood (atro). For many applications, it is particularly practical if the binder is used in step d) in an amount of 1 to 15 wt .-% based on the dry weight of wood (atro). Basically, the inventive method for a

Variety of binder-wood particle combinations suitable. Examples of binders which can be used in the process according to the invention are aminoplasts, phenoplasts, vinyl acetates, isocyanates, epoxy resins and / or acrylic resins. Particularly preferred binders are urea-formaldehyde resin (UF), melamine-formaldehyde resin, phenol-formaldehyde resin (PF),

Polyvinyl acetate and / or white glue. According to a preferred embodiment of the invention, the binder used in step d) is a system based on urea-formaldehyde resins (UF), melamine-reinforced urea-formaldehyde resins (MUF), melamine-urea-phenol-formaldehyde resins (MUPF). , Phenolic Formaldehyde resins (PF), polymeric diisocyanates (PMDI) and / or isocyanates used.

The used in the process according to the invention

Binder may further contain a hardener. Alternatively or additionally, the curing can also by pressing the

Composite material carried out under the action of heat.

Basically, the skilled person various methods

known to glue glued wood particles to a composite material. Practical experiments have shown that in the method according to the invention optimum results are achieved when the pressing in step e) in a

Pressing temperature of at least about 150 ° C is performed.

The selection of wood particle types used in the

can be used according to the invention is almost unlimited. To be particularly suitable

For example, chips, fibers or strands of native wood proven.

The invention furthermore also relates to a wood material which is produced or obtainable by the method according to the invention described here and in its various embodiments.

The invention also includes the intermediates of the process of the invention. These include in particular the treated precursors or intermediates of the wood material.

The invention also relates to a microorganism-containing medium for reducing the content of Wood extract substance, precursors of VOC and / or VOC in a material based on cellulose, in particular wood and / or a wood material, characterized in that the microorganism-containing medium in a bioreactor on cellulose-based material and / or the

Metabolism of wood extractives,

Precursors of VOC and / or VOC has been adapted. In this case, according to further advantageous embodiments of the invention, the microorganism-containing medium, the

Cellulose-based material, the wood-based material, the wood extract, the precursors of VOC, the VOC and the adaptation of the microorganisms as described above for the process according to the invention.

The invention finally also relates to the use of a microorganism-containing medium for reducing the content of Hoizextraktstoff, precursors of VOC and / or VOC in wood or a wood material.

The invention is based on

Embodiments with reference to the accompanying figures described in more detail. The examples serve the

Illustration of the invention and do not limit the scope of the invention.

In the figures show:

FIG. 1 shows a GC-MS / SPME analysis of the hexanal fraction of untreated (control) and with wastewater treatment plant samples (PS, primary sludge, ES, thickening sludge) treated wood chips.

FIG. 2 shows a GC-MS / SPME analysis of the pentanal fraction of untreated (control) and with wastewater treatment plant samples

(PS, primary sludge, ES, thickening sludge) treated wood chips.

FIG. 3 shows a GC-MS / SPME analysis of the hexanal fraction of untreated (control) and wood industry

Wastewater (WSR, Stopfschneckenaustragswasser of a saw chip refiner, WCR, Stopfschneckenaustrasse water of a wood chip refiner) treated wood chips.

Figure 4 shows a GC-MS / SPME analysis of the α-pinene fraction of untreated (control) and treated with a wastewater treatment woodchip biofilter sample (BF) wood chips.

FIG. 5 shows a GC-MS / SPME analysis of the β-pinene fraction of untreated (control) and wood chips treated with a wastewater treatment biofilter sample (BF).

FIG. 6 shows a GC-MS / SPME analysis of the δ-3-carene fraction of untreated (control) and wood chips treated with a wastewater treatment biofilter sample (BF).

FIG. 7 shows a GC-MS / SPME analysis of the hexanal fraction of untreated (control) and wood industry Wastewater (WSR, Stopfschneckenaustragswasser

Saw-chip refiner; CR, Stopfschneckenaustragswasser a wood chip refiner) treated wood strands.

FIG. 8 shows an MS analysis of the aldehyde emission of

Laboratory plates from untreated (control) and wood industry wastewater (WSR, Stopfschneckenaustragswasser a Sägespan-Refiners;

Stopfschneckenaustragswasser a wood chips

Refiners) treated wood strands were made.

The principle of the invention will be explained in more detail below with reference to examples.

example 1

In a laboratory trial were pine wood chips with

treated containing various microorganisms media and then the content of individual VOC (Hexanal and

Pentanal).

As the microorganism-containing medium, various waste water samples were used. All wastewater samples served as a source of food as well as a microbial inoculum.

Part of the wastewater samples comes from a municipal

Wastewater treatment plant in Vienna, Austria. The samples were from

several sites of the clarification cycle like initial treatment (Primary sludge, PS) and thickening (excess sludge, ES) taken.

In addition, wood-industry wastewater from a wood-based material production was tested. For this was

Stopfschneckenaustragswasser a saw chip refiner (WSR) and Stopfschneckenausuhrswasser a wood chip refiner (WCR) during the routine production process

collected.

In the predominantly bacterial microbiocenosis of

Wastewater treatment plant effluents (PS and ES) included species of the Enterobacteriaceae family such as Enterobacter chloacae, Klebsiella sp, Serratia ficaria, Pantoea spp. as well as the

Pseudomonadacea such as Pseudomonas sp detectable.

In the microbiocenoses of the wood industry effluents (WSR and WCR) were among others the bacterial species Klebsiella sp, Pseudomonas sp. and the ubiquitous bacterium Bacillus sp. detectable.

Each 1 gram (wet weight) of pine wood chips was dissolved in 20 ml headspace fine-pitch thread vials (VWR ^®) was weighed and closed with a membrane containing screw cap. All vials were standardized

Sterilization protocol for 15 minutes at 121 ^° C.

autoclaved.

After cooling to room temperature, the tubes were inoculated with 1 ml of the respective effluent (WCR, WSR, PS, and ES). The microorganism density was about 4 × 10 ⁹

Microorganisms of individuals per g of dry wood weight Pine wood chips. To investigate the influence of

Waste water nutrients themselves became additional

Tube prepared with sterilized waste water (WCR

sterile, WSR sterile, PS sterile, and ES sterile). As a further control, a tube with 1 ml of sterile

Tap water offset (control). All experiments were carried out as triplicate.

The tubes were incubated for 7 days at 24 ° C and

then the VOC emissions of the pine wood chips

qualitatively and semi-quantitatively analyzed by SPME / GC-MS analysis.

SPME / GC-MS analysis:

For SPME / GC-MS analysis, a 75 μηα CAR / PDMS fiber (Supelco) was used. The fiber was introduced into the headspace bottles at 30 ° C for 25 minutes. Desorption occurred in an Agilent 7890A at 40 ° C for 400 s. 1 μΐ sample volume was added to the MS HP5 column (30 m × 0.25 mm ID × 0.25 μm)

40 ° C applied. The oven temperature was held at 40 ° C for 4 minutes, then increased linearly from 110 ° C to 4 ° C min ^-1 and continued to increase linearly to 310 ° C at 30 ° C min ^-1 , where it was held for 2 minutes The mass spectrometer was on one

Mass range of 37 to 700 m / z set. With the help of commercially available databases (Wiley, NIST), the substances could be roughly determined. Subsequently, the peak areas between the individual samples (inoculated /

uninoculated / sterile and different effluents).

The comparison of the hexanal fraction in the with

Wastewater effluent (PS and ES) treated samples is considered Bar chart shown in Figure 1. A corresponding comparison of the pentanal fraction is shown in FIG.

The comparison of the hexanal fraction in the wood industry wastewater (WSR and WCR) treated samples is known as

Bar chart shown in Figure 3.

As a result, a significant reduction in aldehyde emissions was observed in the samples treated with wood industry waste water and sewage water. In particular, there was a significant reduction in their pentanal and

Hexanal emissions compared to untreated samples. The results indicate that the microbial

Growth for the consumption of VOC (especially aldehydes) and their precursors (especially fatty acids) leads.

SPME analysis: The treated chips and the chips from the untreated control samples were freeze-dried and then subjected to solid phase micro extraction extraction analysis

(SPME) used. The extraction was carried out with a Buchi SpeedExtractor E-916. The procedure consisted of four

Extraction cycles (5 minutes each) and one

Extraction mixture of 95/5 acetone-water (v / v) at 110 bar and 110 ° C. From the extracts contained in each case 1.5 ml sample volume was transferred to a Pyrex tube and mixed with 100 μΐ internal standard (ISTD). The internal standard was 6 mg heneicosanoic acid, 9 mg Cholesteryl palmitate, 9 mg 1, 3-dipalmitoyl-2-deyl-glycerol, 9 mg Betulin dissolved in 12 ml acetone.

After vacuum evaporation of the solvent followed the

Derivatization with 80 μM BSTFA (N, O-bis-trimethylsilyl trifluoroacetamide, Sigma), 20 μM TMCS (trimethylchlorosilane, Sigma) and 20 μM pyridine at 70 ° C for 45 min. in the

sealed Pyrex tubes. The samples were injected at 270 ° C and separated on a MS HP5 column (30 m x 0.25 mm ID x 0.25 μm). The

Oven temperature was maintained at 100 ° C for 1 min, then ramped up from linear to 325 ° C at 5 ° C min ^-1 and was then held for 14 min. The mass spectrometer was set to a mass range of 37 to 700 m / z. A

Approximate quantification was possible by multiplying the known amount of ISTD by the quotient of the substance peak area and the ISTD peak area. This was done assuming that the response factors were identical for all substances analyzed and that the

Calibration curves in the detection range were linear.

Example 2

Pine wood shavings were treated and tested as described in Example 1, except that the microorganism-containing medium contained a sample from the upstream one

Wood chip biofilter (BF) of a municipal sewage treatment plant was used and as VOCs various terpenes (a-pinene, ß-pinene and δ-3-carene) was analyzed by GC-MS / SPME analysis. The comparison of the pinene, β-pinene and δ-3-carene fraction in the wood chips treated with the wood chip biofilter sample (BF) is shown as a bar chart in FIGS. 4, 5 and 6.

As a result, a significant reduction in terpene emissions was observed in wood chips treated with the woodchip biofilter sample (BF). In particular, there was a significant reduction in their α-pinene, β-pinene and δ-3 carene emissions compared to untreated samples. The results indicate that the

microbial growth also leads to the consumption of terpene VOCs and / or their precursors.

Example 3

In another attempt was on a larger scale

worked and pressed from the treated wood particles laboratory plates.

For treatment, the same wood industry effluents (WCR and WSR) were used as in Example 1. 36 kg fresh pinewood strands with a moisture content of 58% were equivalently divided into 36 polyethylene zip-lock bags (40 x 60 cm ² , 50 μm thick) and subsequently

gamma sterilized (dose: 25.5 kGy min according to ISO 9001: 2008). Twelve of the sterilized bags were inoculated with the wastewater WSR and WCR. 200 ml of the respective waste water were added to each aliquot. The microorganism density was about 1 x 10 ⁹ microorganisms individuals per g Wood dry weight of pine wood strands. The wood moisture was 243%.

12 control samples were instead taken with 200 ml

spiked with sterilized water. All bags were incubated for 6 weeks at 23 ° C.

Subsequently, the aliquots of each group (control, WSR and WCR) were combined and dried successively in a rotary drum dryer for about 4 hours at a supply air of about 35 m ³ h ^"1 and a supply air temperature of 180 ^° C.

Moisture content of the dried material was approx.

4.0% (untreated strands = control) and 4.8 / 5.2% (WSR / WCR treated strands).

The VOC content of the wood industrial wastewater treated samples and control samples was determined by GC-MS as described above. A comparison of the Hexanal fraction of wood treated wastewater (WSR and WCR) treated strands is known as

Bar chart shown in Figure 7. As a result, there was a significant reduction in hexanal values compared to untreated beaches.

From the treated strands and the control samples, laboratory plates were subsequently prepared according to the protocol given in Table 1. Table 1

From the laboratory plates, 41 sample plates (0 43, 5 mm) per laboratory plate for the VOC were made 41 days after preparation

Measurements cut. The sample disks were placed in separate PCTE ™ microcompartments / Thermal Extractors (Markes ^®) and the VOC content at day 3, 7, 17 and 28 after

Microcompartment storage measured. The area-specific air exchange rate was set to 0, 5 m ³ xm ^{~ 2} xh ^-1 .

Otherwise, the test parameters were set and the VOC measurement protocol used as described in Stratev, D., Gradinger, C, Ters, T., Fackler, K., Kuncinger, T., Srebotnik, E. (2011) "Fungal pretreatment of pine wood to reduce the emission of volatile organic compounds ", Holzforschung (65).

Individual VOCs were analyzed by mass spectrometry (MS)

identified. The peak integration was semiautomatic by the Agilent MSD Chemstation software

(Agilent). The content of pentanal, hexanal and octanal was quantified, added and presented as "total aldehydes". The quantification was done with external calibration with authentic standards and d8-toluenes as internal standard.

As an exemplary result of the micro chamber measurements, Figure 8 shows the comparison of the "total aldehydes" fractions of the slabs produced from strands treated with wood industry waste water (WSR and WCR).

Sheets of treated strands showed a significant reduction in their aldehyde emissions as compared to non-treated strands. The results indicate that microbial growth is responsible for the consumption of VOC

(especially aldehydes) and their precursors

(especially fatty acids) leads.

Claims

claims

A process for producing a wood material, characterized in that a wood-containing intermediate or intermediate product of the wood material with a

Treated medium containing microorganisms.

A method according to claim 1, characterized in that the microorganisms contained in the medium are a Mikrobiozönose.

A method according to claim 1 or 2, characterized

characterized in that the microorganisms contained in the medium were obtained from wastewater and / or filter residues from the treatment of this wastewater.

Method according to one of the preceding claims, characterized in that the microorganism-containing medium contains wastewater and / or filter residues from the treatment of this wastewater or consists thereof.

A method according to claim 3 or 4, characterized

characterized in that the wastewater is selected from the group consisting of precipitation water, domestic sewage, municipal sewage, industrial waste water,

Wastewater from water treatment plants and combinations thereof.

Method according to one of claims 3 to 5, characterized in that the wastewater is an AI

that with wood and / or wood components i has come, in particular wastewater from the wood and / or woodworking industry.

7. The method according to claim 6, characterized in that the wastewater from the wood material production, in particular from the treatment of wood by steaming, cooking, fiberizing or drying, comes.

8. Method according to one of the preceding claims,

characterized in that the microorganisms contained in the medium of biofilms and / or living substances in the form of activated sludge

Sewage treatment plants or wastewater from a woodchip biofilter of a sewage treatment plant.

9. Method according to one of the preceding claims,

characterized in that the microorganism-containing medium contains biofilms and / or living substances in the form of activated sludge from sewage treatment plants or wastewater from a woodchip biofilter a sewage treatment plant or consists of these.

10. The method according to claim 8 or 9, characterized

characterized in that the activated sludge from sewage treatment plants is selected from the group consisting of sludge of the aerobic or anaerobic treatment basin, excess sludge of the aerobic or anaerobic treatment basin, sludge from the digester, primary sludge and combinations thereof.

11. The method according to any one of the preceding claims,

characterized in that the medium containing microorganisms before use in the

process according to the invention in a bioreactor Material based on cellulose and / or the

Metabolism of wood extractives,

Precursors of VOC and / or VOC was adapted.

Method according to one of the preceding claims, characterized in that in the medium

At least about 50%, preferably at least about 80% and more preferably at least about 90% of the contained microorganisms are bacteria.

Method according to one of the preceding claims, characterized in that the microorganism-containing medium at least one bacterial strain

which is selected from the group consisting of Enterobacteriacea, in particular Enterobacter chloacae, Klebsiella sp. , Serratia ficaria, Pantoea spp. .

Pseudomonadacea, in particular Pseudomonas sp. and Bacillus sp.

Method according to one of the preceding claims, characterized in that the medium

Microorganisms in a total of at least about 10 ⁴ microorganisms / ml, preferably at least about 10 ^s microorganisms / ml and more preferably at least about 10 ⁶ microorganisms / ml.

Method according to one of the preceding claims, characterized in that the wood-containing precursor or intermediate product of the wood material in the

Treatment with the microorganism-containing medium has a wood moisture content of at most 300%, preferably at most 250% and particularly preferably from 130 to 250%,

having .

16. The method according to any one of the preceding claims, characterized in that in the treatment with the microorganism-containing medium a

Microorganism density of at least about 1 x 10 ³ , preferably at least about 1 x 10 ⁴ , more preferably at least about 1 x 10 ⁵ or at least about 1 x 10 ⁶ microorganisms individual organisms per g of wood

containing pre- or intermediate product is present.

17. The method according to any one of the preceding claims,

characterized in that the process results in a reduction in the content of wood extract,

Precursors of VOC and / or VOC in the wood material leads.

18. The method according to any one of the preceding claims,

characterized in that the wood material is a pressed wood material, in particular a fiber or OSB board.

19. The method according to claim 18, characterized in that the wood-containing precursor or intermediate product of the wood material are wood particles and the method comprises at least the following steps: a) bringing into contact with wood particles

Microorganism-containing medium; b) incubation of the material from step a); c) drying the pretreated wood particles at 80 to 400 ° C; d) Beieimen the pretreated wood particles with a

Binder; and e) pressing the mixture into a pressed one

Wood material.

Wood material produced by a process according to one of claims 1 to 19.

Microorganism-containing medium for reducing the content of wood extract, precursors of VOC and / or VOC in a material based on cellulose, in particular wood and / or a wood material, characterized in that the microorganism-containing medium in a bioreactor on cellulose-based material and / or the metabolism of

Wood extracts, precursors of VOC and / or VOC has been adapted.

A microorganism-containing medium according to claim 20, characterized in that the microorganism-containing medium is as defined in any one of claims 2 to 10 and / or 12 to 14.

Use of a microorganism-containing medium for reducing the content of wood extract,

Precursors of VOC and / or VOC in wood or a wood-based material.